CN117318489A - Power conversion device - Google Patents

Abstract

The invention provides a power conversion device which can reduce the number of components and cool a semiconductor element on a secondary side with a simple structure at low cost. Comprising the following steps: a plurality of semiconductor switching elements (4 a-4 d) for converting a DC voltage (Vin) into an AC voltage; an insulation transformer (2) for transmitting the alternating voltage from the primary side to the secondary side and outputting the alternating voltage; and a rectifying circuit (5) including a plurality of diodes (5 a, 5 b) for rectifying the output, wherein the plurality of semiconductor switching elements (4 a-4 d) and the plurality of diodes (5 a, 5 b) are formed by modules sealed in the same package.

Description

Power conversion device

Technical field

This application relates to power conversion devices.

Background technique

In order to charge a low-voltage lead battery from a high-voltage lithium-ion battery, a DC/DC converter is installed in electrified vehicles such as electric cars and hybrid cars. For the purpose of protection from high voltage, high-voltage lithium-ion batteries are insulated from the chassis or low-voltage system. DC/DC converters generally require an isolation transformer to connect the high-voltage input side to the low-voltage output side. insulation. At this time, the DC input voltage is switched by a semiconductor element, etc., converted into an AC signal, etc., and is input to the primary side of the insulation transformer. The output of the secondary side of the insulation transformer is rectified by the semiconductor element, etc., as a DC signal. The output voltage.

The current flowing through the secondary side of the DC/DC converter of an electric vehicle often requires a current of more than several hundred A. Ordinary glass epoxy substrates are difficult to apply due to their small copper thickness and large temperature rise caused by losses. . Therefore, for example, in Patent Document 1, a copper plate with a certain thickness is used as a wiring, surface-mounted discrete semiconductor elements are mounted on the copper plate, and the copper plate is fixed to a cooler to suppress the temperature rise of the wiring due to large current , and cool discrete semiconductor components.

existing technical documents

patent documents

Patent Document 1: Japanese Patent No. 6516910

Contents of the invention

The technical problem to be solved by the invention

In order to ensure the cooling of discrete semiconductor components mounted on a copper plate, the copper plate needs to be reliably fixed on the cooler. Not only the copper plate is needed as a wiring, but also the screws or bushings for fixing the copper plate. The number of parts is large, not only in terms of materials. , also expensive to manufacture. In addition, in order to ensure the flatness and strength of the copper plate for input and output wiring of discrete components, the copper plate needs to be insert-molded, which is also a major factor in increasing costs. Furthermore, it is necessary to arrange a plurality of discrete semiconductor elements according to the output current, thereby increasing the size of the copper plate. In order to fix the enlarged sheet metal, the number of screws increases, and the copper plate becomes enlarged, which increases the area required for cooling and makes the cooler expensive. In particular, in circuit structures where the copper plate that cools discrete semiconductor components needs to be insulated from the cooler, if insulation reliability is to be ensured, the thickness of the grease or gap filler between the copper plate and the cooler needs to be increased, thereby cooling performance deterioration, and the increase in discrete semiconductor components or the enlargement of copper plates hinders cost reduction.

This application discloses a technology for solving the above-mentioned problems, and aims to provide a power conversion device that can reduce the number of components and cool secondary-side semiconductor elements with a simple structure at low cost.

Technical means used to solve technical problems

The power conversion device disclosed in this application is characterized by including: a plurality of semiconductor switching elements that convert the DC voltage of the DC power supply into an AC voltage; and an insulation transformer that converts the AC voltage from a primary voltage to an AC voltage. side is transmitted to the secondary side and output; and a rectification circuit, the rectification circuit includes a plurality of rectification elements for rectifying the output,

The plurality of semiconductor switching elements and the plurality of rectifying elements are composed of modules sealed in the same package.

Invention effect

According to the power conversion device disclosed in the present application, it is possible to obtain a power conversion device that can reduce the number of components and can cool a secondary-side semiconductor element at low cost with a simple structure.

Description of drawings

FIG. 1 is a circuit diagram of the power conversion device according to Embodiment 1.

FIG. 2 is a diagram showing the internal structure of a module of the power conversion device according to Embodiment 1. FIG.

FIG. 3 is a diagram showing the mounting structure of the power conversion device according to Embodiment 1. FIG.

FIG. 4 is a side view showing the mounting structure of the power conversion device according to Embodiment 1. FIG.

FIG. 5 is a circuit diagram of the power conversion device according to Embodiment 2.

FIG. 6 is a side view showing the mounting structure of the power conversion device according to Embodiment 2. FIG.

FIG. 7 is a plan view showing the mounting structure of the power conversion device according to Embodiment 2. FIG.

FIG. 8 is a side view showing another example of the mounting structure of the power conversion device according to Embodiment 2. FIG.

Detailed ways

Hereinafter, preferred embodiments of the power conversion device according to the present application will be described using the drawings. In addition, in each drawing, the same or corresponding member and part are attached|subjected with the same code|symbol, and are demonstrated.

Embodiment 1.

FIG. 1 is a circuit configuration diagram of the power conversion device according to Embodiment 1. As shown in FIG. 1 , the power conversion device 100 converts the DC voltage Vin of the DC power supply 1 into a secondary-side DC voltage insulated by the transformer 2 , and outputs the DC voltage Vout to a load 3 such as a battery, for example.

The power conversion device 100 includes: an insulated transformer 2; a single-phase inverter 4 connected to the primary winding 2a of the transformer 2 and as a MOSFET having a diode built-in between the source and the drain. The formed semiconductor switching elements 4a to 4d constitute a full-bridge structure, an inverter that converts the DC voltage Vin of the DC power supply 1 into an AC voltage; and a rectifier circuit 5 connected to the secondary winding 2b of the transformer 2 and configured There are diodes 5a and 5b which are rectifier elements that are semiconductor elements. In addition, the filter reactor 6 and the filter capacitor 7 for output filtering are connected to the output of the rectifier circuit 5 and output the DC voltage Vout to the load 3 . The secondary side of the transformer 2 is a center-tap type, and the center-tap terminal is connected to GND, and the other secondary side terminals are connected to the anode terminals of the diodes 5a and 5b respectively. The cathode terminals of the diodes 5a, 5b are connected to the filter reactor 6.

In the above content, as an example of the power conversion device 100, an example in which the secondary side is a center-tapped DC/DC converter is shown. However, the secondary side may also be a full-bridge structure. As the rectifying element, Example of a diode, but could also be a MOSFET. In addition, an example of a DC/DC converter with a full-bridge primary side is shown, but any converter may be used as long as it is an isolation-type converter such as a forward type, a flyback type, an LLC type, etc., which has an isolation transformer. In addition, the semiconductor switching elements 4a to 4d are not limited to MOSFETs, and may be self-extinguishing semiconductor switching elements such as IGBT (Insulated Gate Bipolar Transistor) in which a diode is connected in antiparallel. The same applies to the case where the rectifying element is a MOSFET.

Next, the structure of a module in which the primary-side semiconductor switching elements 4a to 4d and the secondary-side diodes 5a and 5b are sealed in the same package in this embodiment will be described with reference to FIGS. 2(a) and 2(b). In addition, in FIG. 2(a) and FIG. 2(b), the same reference numerals are used to describe parts corresponding to those in FIG. 1 .

FIG. 2(a) is a top perspective view of the module 8, and FIG. 2(b) is a cross-sectional perspective view from the front direction of FIG. 2(a). The cross-sectional structure of the module 8 is explained with reference to FIG. 2 .

The semiconductor switching elements 4a to 4d are, for example, semiconductor chips each having a drain pad on the bottom surface and gate pads 40a to 40d and source pads 41a to 41d on the upper surface. The semiconductor switching elements 4a to 4d are respectively mounted on the lead frames 42a to 42d. The diodes 5 a and 5 b have, for example, a cathode pad on the bottom surface and an anode pad on the upper surface, and are mounted on the lead frame 43 .

Reference numerals 44, 45a to 45d, 46a to 46d, 47a, and 47b represent lead frames. The lead frames 43, 44, 42a to 42d, 45a to 45d, 46a to 46d, 47a, and 47b are insulated from the cooling plate 9 by the insulating member 10. Module 8 in which semiconductor switching elements 4a to 4d, diodes 5a and 5b, lead frames 43, 44, 42a to 42d, 45a to 45d, 46a to 46d, 47a, 47b, cooling plate 9, and insulating member 10 are exposed to the cooling plate 9 The surface in the bottom direction is molded with resin 11. In addition, the lead frames 42a to 42d, 43, 44, 45a to 45d, 46a to 46d, 47a, and 47b are bent toward the upper surface direction of the module 8 to form external terminals. In the cross-sectional perspective view of FIG. 2(b) , connection wiring such as bonding is omitted.

Next, a top perspective view of the module 8 shown in Fig. 2(a) will be explained.

The drain pad of the semiconductor switching element 4a is mounted on a lead frame 42a, and the lead frame 42a is connected to the positive electrode of the DC power supply 1 via, for example, a wiring pattern of a glass epoxy substrate. The source pad 41 a of the semiconductor switching element 4 a is connected to a lead frame 42 b via a wire bonding 48 a, and the lead frame 42 b is connected to the primary winding 2 a of the transformer 2 via a wiring pattern of a glass epoxy substrate or the like.

The drain pad of the semiconductor switching element 4b is mounted on the lead frame 42b. The source pad 41 b of the semiconductor switching element 4 b is connected to a lead frame 44 via a wire bonding 48 b, and the lead frame 44 is connected to the negative electrode of the DC power supply 1 via a wiring pattern of a glass epoxy substrate or the like.

The drain pad of the semiconductor switching element 4c is mounted on a lead frame 42c, and the lead frame 42c is connected to the positive electrode of the DC power supply 1 via a wiring pattern of a glass epoxy substrate or the like.

The source pad 41 c of the semiconductor switching element 4 c is connected to a lead frame 42 d via a wire bonding 48 c, and the lead frame 42 d is connected to the primary winding 2 a of the transformer 2 via a wiring pattern of a glass epoxy substrate or the like.

The drain pad of the semiconductor switching element 4d is mounted on the lead frame 42d. The source pad 41d of the semiconductor switching element 4d is connected to the lead frame 44 through the wire bonding 48d.

In addition, the gate pads 40a to 40d of the semiconductor switching elements 4a to 4d are respectively connected to the lead frames 45a to 45d through wire bonds 49a to 49d. The lead frames 45a to 45d are connected to the gate circuit mounted on the glass epoxy substrate via the wiring pattern of the glass epoxy substrate. In addition, the reference potentials for gate driving of the semiconductor switching elements 4a to 4d are connected to the lead frames 46a to 46d from the respective source pads 41a to 41d via wire bonds 50a to 50d. The lead frames 46a to 46d are connected to the reference potential of each gate circuit mounted on the glass epoxy substrate via the wiring pattern of the glass epoxy substrate.

In the above description, an example has been shown in which the reference potentials for gate driving of the semiconductor switching elements 4a to 4d are connected from the source pads 41a to 41d to the lead frames 46a to 46d respectively through the wire bonds 50a to 50d. However, they may also be connected. The gate driving pads are provided on the semiconductor switching elements 4a to 4d separately from the source pads 41a to 41d, and the gate driving reference potentials of the semiconductor switching elements 4a to 4d are connected from the semiconductor switching elements 4a to 4d through the wire bonds 50a to 50d, respectively. Each gate driving pad is connected to the lead frames 46a to 46d.

The diode 5a is connected from the anode pad 51a to a lead frame 47a by wire bonding 52a, and the lead frame 47a is connected to the secondary winding 2b of the transformer 2 by, for example, soldering or welding. The diode 5b is connected from the anode pad 51b to a lead frame 47b by wire bonding 52b, and the lead frame 47b is connected to the secondary winding 2b of the transformer 2 by, for example, soldering or welding. Furthermore, the cathode pads of the diodes 5 a and 5 b are mounted on a common lead frame 43 , and the lead frame 43 is connected to the filter reactor 6 .

Here, the lead frames 42a to 42d, 44, 45a to 45d, and 46a to 46d are primary side external terminals, and the lead frames 43, 47a, and 47b are secondary side external terminals. In addition, the lead frames 42a, 42c, and 44 serve as primary-side DC input terminals among the primary-side external terminals, and the lead frames 42b and 42d serve as primary-side AC output terminals among the primary-side external terminals. In addition, the lead frames 47a and 47b serve as secondary-side AC input terminals among the secondary-side external terminals, and the lead frame 43 serves as a secondary-side DC output terminal.

The lead frames 42 b and 42 d may be connected on a glass epoxy substrate on the outside of the module 8 , or may be connected inside the module by installing a bus bar across the lead frame 44 . In addition, although the example in which the number of gate wire bonds 49a to 49d is one and the number of drain wire bonds is three is shown, the number is not limited to this. Also, bus bars instead of wire bonds are possible.

Next, a method of mounting the power converter device in a case accommodating the power converter device according to this embodiment will be described with reference to FIGS. 3(a) and 3(b). FIG. 3(a) is a plan view showing the mounting structure of the power conversion device 100, and FIG. 3(b) is a left side view showing the connection relationship of external terminals.

In Figure 3 (a) and Figure 3 (b), the housing 12 is provided with an inlet 14 to a water path 13 of cooling water and an outlet 15 from the water path 13. The cooling water is used to cool the power conversion device. The refrigerant of the main heating components of 100 is the module 8, the transformer 2, and the filter reactor 6. The housing 12 functions as a cooler, with the cooling water flowing through the water path 13, in the normal direction of which the modules 8 are stacked. Module 8, transformer 2, and filter reactor 6 are installed on the projection surface of waterway 13. The base plate 16 is mounted to overlap the module 8 . At this time, it may overlap with at least part of the transformer 2 and the filter reactor 6 . In the module 8, the same reference numerals are used to denote the parts common to those in FIG. 2. Only the semiconductor switching elements 4a to 4d constituting the inverter 4 and the diodes 5a and 5b constituting the rectifier circuit 5 are shown, and the cooling plate 9 and insulation are omitted. Component 10 and bonding wires, etc.

In Figure 3(a), the inverter 4 is installed in the left area of the module 8, and the rectifier circuit 5 is installed in the right area of the module 8. Lead frames 42a, 42c, 44 as external terminals for connecting the inverter 4 to the DC power supply 1 are located on the side of the module 8 opposite the filter reactor 6, and are separated from each other as gate terminals of the semiconductor switching elements 4a, 4c. The lead frames 45a and 45c pass together through a through hole provided in the substrate 16 and are connected to the substrate 16 by solder or the like. Lead frames 42b, 42d as external terminals for connecting the inverter 4 to the transformer 2 are located on the side of the module 8 opposite the transformer 2, and lead frames 45b, 45d as respective gate terminals of the semiconductor switching elements 4b, 4d Together, they pass through a through hole provided on the substrate 16 and are connected to the substrate 16 by solder or the like.

Lead frames 47a, 47b as external terminals connecting the rectifier circuit 5 to the transformer 2 are located on the side of the module 8 opposite to the transformer 2, and a lead frame 43 as an external terminal connected to the filter reactor 6 is located on the side of the module 8 opposite to the filter reactor 6. 6 opposite sides of the device. The terminals 53, 54, 55, and 56 of the transformer 2 are all located on the module 8 side. The terminals 53 and 54 connected to the inverter 4 are connected to the substrate 16 through the through holes provided on the substrate 16 through solder or the like, and are connected to the substrate 16 through the substrate 16. The wiring 17 on the module 8 is respectively connected to the lead frames 42b, 42d as external terminals of the module 8. Furthermore, the terminals 55 and 56 of the transformer 2 connected to the rectifier circuit 5 are arranged to face the lead frames 47 a and 47 b respectively as external terminals of the module 8 and are connected to the lead frames 47 a and 47 b by, for example, soldering.

A lead frame 43 as an external terminal connecting the rectifier circuit 5 to the filter reactor 6 is located on the side of the module 8 opposite to the filter reactor 6 and is connected to the terminal 18 of the filter reactor 6 by, for example, welding or the like.

FIG. 4 shows the positional relationship between the housing 12 , the water channel 13 , the module 8 , the inverter 4 and the rectifier circuit 5 . The water channel 13 provided inside the casing 12 is a flat water channel. The module 8 is arranged on the projection surface of the water channel 13 and is mounted on the casing 12 through a cooling member 19 such as grease or gap filler. Furthermore, the semiconductor switching elements 4 a to 4 d constituting the inverter 4 and the diodes 5 a and 5 b constituting the rectifier circuit 5 are cooled by the water passage 13 via the cooling member 19 and the casing 12 .

According to the above embodiment, the semiconductor switching elements 4a to 4d on the primary side of the DC/DC converter and the diodes 5a and 5b on the secondary side are used as the module 8 sealed in the same package, thereby eliminating the need for the diodes 5a and 5b. The cooling structure inherent in the secondary side, which is necessary for discrete packages, includes sheet metal for mounting discrete packages, bushings and screws for fixing, and resin insertion to ensure the flatness and strength of the sheet metal. It can reduce the number of parts and enable Cooling structures are cheap. In addition, since miniaturization is achieved by reducing the number of components, the area required for cooling can be reduced, and by miniaturizing the case 12, the diodes 5a, 5b can be cooled at low cost.

In addition, by using the same semiconductor chip as the diodes 5a and 5b on the secondary side and setting it as a module integrated with the semiconductor switching elements 4a to 4d on the primary side that also require cooling, it is possible to share the same with the semiconductor switching elements 4a to 4d. The cooling plate 9 can thereby reduce the cost of cooling the diodes 5a and 5b. In addition, by sharing the insulating member 10 with the semiconductor switching elements 4a to 4d that need to be insulated from the case 12, the cost of insulating the diodes 5a, 5b from the case 12 can be reduced.

In this embodiment, an example of a circuit structure is shown in which the center tap of the transformer 2 is connected to GND, and the diodes 5a, 5b are at a different potential from GND, but it can also be applied to the case where the center tap of the transformer 2 is connected to the filter reactor 6 , a circuit structure in which the anode terminals of diodes 5a and 5b are connected to GND. In this case, the anodes of the diodes 5a, 5b can be connected to the cooling plate 9, so that the insulating member 10 on the projected surface of the lead frame 47a, 47b on which the anode terminal of the diode 5a, 5b is mounted is not required, thereby enabling cost reduction. .

In this embodiment, since the primary-side semiconductor switching elements 4a to 4d constitute a full-bridge circuit, the number of elements is large, and there is no need for package parts other than chips and gaps between packages required for discrete semiconductors. The semiconductor switches are The module 8 in which the elements 4a to 4d and the secondary-side diodes 5a and 5b are sealed in the same package has a better effect of miniaturization. Thereby, the area required for cooling can be reduced, and the cooler can be miniaturized. In addition, since the full-bridge circuit can generally cope with a large output power, in applications with a large output power, when the cooling structure of the secondary-side diodes 5a and 5b becomes the main reason for further increase in cost, it can be reduced The number of components of the cooling structure can make the cooling structure cheaper and more effective.

In this embodiment, since the diodes 5a and 5b are used as rectifying elements on the secondary side, gate terminals required for switching elements such as MOSFETs are not required, and the number of terminals is small. Therefore, the external terminal arrangement of the module 8 is long. The size in the side direction is not limited by the number of terminals, and the module 8 can be miniaturized. Thereby, the area required for cooling can be reduced, and the cooler can be miniaturized.

In this embodiment, since the lead frames 43, 44, 42a to 42d, 45a to 45d, 46a to 46d, 47a, and 47b as external terminals of the module 8 are arranged on both sides of the side surface of the module 8, the module 8 can be placed in a long position. The size can be reduced in the side direction without being limited by the gap between the terminal width and the external terminal due to strength, which is a problem when concentrated on one side, or heat generation due to conduction current. In addition, in order to shorten the lead frame and the bonding wire, the semiconductor switching elements 4a to 4d and the diodes 5a and 5b are usually arranged near the corresponding external terminals. Therefore, by arranging the external terminals on both sides of the side of the module 8, the semiconductor switching elements can be The mounting areas of 4a to 4d and diodes 5a and 5b are close to each other. Thereby, the area required for cooling can be reduced, and the cooler can be miniaturized.

In addition, in this embodiment, since the inverter 4 composed of the semiconductor switching elements 4a to 4d and the rectifier circuit 5 composed of the diodes 5a and 5b are arranged in the same direction as the external terminals are arranged (that is, the length of the module 8 side direction), therefore, the lead frames 42a to 42d, 44, 45a to 45d, and 46a to 46d, which are external terminals connected to the inverter 4 composed of the semiconductor switching elements 4a to 4d, can be arranged near the inverter 4 . In addition, the lead frames 43 , 47 a , and 47 b serving as external terminals connected to the rectifier circuit 5 composed of the diodes 5 a and 5 b may be arranged near the rectifier circuit 5 . This can suppress the increase in the size of the module 8 due to the routing of unnecessary wiring, and can also suppress noise or surges caused by the lengthening of the wiring.

In addition, in this embodiment, the lead frames 42a, 42c, and 44 serving as input external terminals of the inverter 4 composed of the semiconductor switching elements 4a to 4d and connected to the DC power supply 1 are located on the first side of the module 8 (Fig. 2 ), the lead frames 42 b and 42 d serving as output external terminals of the inverter 4 connected to the primary winding 2 a of the transformer 2 are located on the second side of the module 8 (the upper side in FIG. 2 ). In addition, the lead frames 47a and 47b as input external terminals of the rectifier circuit 5 composed of the diodes 5a and 5b connected to the secondary winding 2b of the transformer 2 are located on the second side of the module 8 (the upper side in FIG. 2), and the rectifier The lead frame 43 as an output external terminal of the circuit 5 connected to the filter reactor 6 is located on the first side of the module 8 (the lower side in FIG. 2 ). Therefore, the input external terminals and the output external terminals of the inverter 4 and the rectifier circuit 5 can be arranged on different sides of the module 8, and the module 8 can be miniaturized in the longitudinal direction.

In addition, in order to shorten the lead frame or the bonding wire, the semiconductor switching elements 4a to 4d and the diodes 5a and 5b are usually arranged near the corresponding external terminals. Therefore, by arranging the external terminals on both sides of the module 8, the semiconductor switching elements can be 4a to 4d and the mounting areas of the diodes 5a and 5b are close to each other, so that the area required for cooling can be reduced and the cooler can be miniaturized. In addition, since the lead frames 42b, 42d, 47a, 47b as external terminals connected to the transformer 2 are located on the second side (upper side in FIG. 2) of the module 8, the connection wiring to the transformer 2 can be shortened and the cost can be reduced.

In this embodiment, an example is shown in which the lead frames 42a to 42d, 43, 44, 45a to 45d, 46a to 46d, 47a, and 47b as external terminals of the module 8 are arranged on both sides of the side surface of the module 8. However, A part of the lead frame serving as the external terminal may be arranged in the short side direction. For example, the lead frames 42a, 42c, and 44 serving as input external terminals of the inverter 4 composed of the semiconductor switching elements 4a to 4d and connected to the DC power supply 1 may be located on the third side (left side in FIG. 2) of the module 8. , the lead frame 43 serving as an output external terminal of the rectifier circuit 5 composed of the diodes 5 a and 5 b connected to the filter reactor 6 may be located on the fourth side (right side in FIG. 2 ) of the module 8 . When the connection interface with the DC power supply 1 is located on the left side of the module 8 in FIG. 2 , or when the filter reactor 6 is arranged on the right side of the module 8 on the right side of the module 8 in FIG. 2 , the module 8 can be shortened. The connection interface with the DC power supply 1 or the connection with the filter reactor 6 is wired and the cost is reduced.

In this embodiment, since the cooler for cooling the module 8 is provided including the housing 12 and the water passage 13, for example, in an application with a large output power, in order to improve the semiconductor switching elements 4a to 4d and the diode 5a When the size of the lead frames 42a to 42d and 43 is limited due to the heat dissipation of , 5b, the lead frames 42a to 42d and 43 can be reduced, the module 8 can be miniaturized, and the cooling system composed of the housing 12 and the water channel 13 can be reduced. Miniaturization of the device. As a result, the cost of the power conversion device 100 can be reduced.

In addition, since the cooling water flows in the direction perpendicular to the direction in which the inverter 4 and the rectifier circuit 5 of the module 8 are arranged, the inverter 4 and the rectifier circuit 5 of the module 8 are not cooled by a rise in temperature due to mutual heat generation. Water effects. Therefore, the temperature rise can be suppressed and the module 8 can be miniaturized. As a result, the cooler composed of the casing 12 and the water passage 13 can be miniaturized, and the cost of the power conversion device 100 can be reduced.

In addition, since part of the transformer 2 and the filter reactor 6 are located outside the projection surface of the water channel 13, priority is given to the module 8 that has a larger cooling area relative to the height than the transformer 2 and the filter reactor 6, and therefore has a higher cooling efficiency in the water channel 13. The inverter 4 and the rectifier circuit 5 are arranged in the water channel 13, so that the module 8 can be miniaturized, and the cooler composed of the casing 12 and the water channel 13 can be miniaturized. As a result, the cost of the power conversion device 100 can be reduced.

Embodiment 2.

Next, the power conversion device according to Embodiment 2 will be described. FIG. 5 is a circuit diagram of the power conversion device according to Embodiment 2.

As shown in FIG. 5 , a power conversion device 300 according to Embodiment 2 is configured by combining a power conversion device 200 including, for example, a vehicle driving electric motor, which is separately driven, with the power conversion device 100 described in Embodiment 1. 60, 61 inverters 62, 63.

An input capacitor 64 for stabilizing the DC input voltage is connected in parallel with the DC power supply 1 , and a boosting reactor 65 is connected to the positive side of the input capacitor 64 . The output of the boosting reactor 65 is connected to the midpoint of the half-bridge switching element 66 , and the boosting reactor 65 and the half-bridge switching element 66 constitute a boosting chopper. The output of the half-bridge switching element 66 is filtered by a filter capacitor 67 . Inverter 62 is connected with filter capacitor 67 as input, and the three-phase output lines of inverter 62 are connected to electric motor 60 . In addition, the regeneration inverter 63 is connected in parallel with the inverter 62, and is connected to the motor 61 through a three-phase line. By boosting the voltage using the boost chopper composed of the boost reactor 65 and the half-bridge switching element 66, the wiring from the filter capacitor 67 to the inverters 62 and 63 can be reduced under the same power condition. Current from the inverters 62, 63 to the respective electric motors 60, 61. This can make the wiring thinner, which has the advantages of cost reduction and weight reduction. The half-bridge switching element 66 is, for example, an IGBT in which diodes are connected in antiparallel.

The internal structure of the module 8 of the power conversion device 100 constituting the power conversion device 300 of this embodiment and the mounting structure of the power conversion device 100 are the same as those in FIGS. 2 and 3 respectively, and detailed descriptions are omitted. FIG. 6 shows the positional relationship between the casing 12 and the water passage 13 , the module 8 of the power conversion device 100 , and the required structural members of the power conversion device 200 , and is a diagram only illustrating the differences from FIG. 4 . The same components as in FIG. 4 are shown using the same reference numerals.

In FIG. 6 , the housing 12 is provided with, for example, a flat water passage 13 , and the half-bridge switching element 66 and the inverters 62 and 63 are installed in the housing 12 via a second cooling member 70 such as grease or gap material. on the second surface 69 on the opposite side parallel to the first surface 68 of the module 8 on which the power conversion device 100 is installed. The input capacitor 64, the boosting reactor 65, and the filter capacitor 67 are omitted in FIG. 6 . The half-bridge switching element 66 and the inverters 62 and 63 are respectively modularized and arranged in the same direction as the inverter 4 and the rectifier circuit 5 of the module 8 are arranged. In addition, the half-bridge switching element 66 and the inverters 62 and 63 have a cooling surface having the same structure as the module 8 , and the cooling surface faces the second cooling member 70 . The arrangement order of the half-bridge switching element 66 and the inverters 62 and 63 is an example, and may be any arrangement order. In addition, fins 72 for increasing the cooling capacity of the second surface 69 of the housing 12 are arranged on the third surface 71 of the water passage 13 that faces the second surface 69 of the housing 12 . The heat generated by the half-bridge switching element 66 and the inverters 62 and 63 is dissipated into the water passage 13 via the second cooling member 70 , the housing 12 , and the fins 72 .

FIG. 7 is a plan view showing the positional relationship between the water passage 13 and the fins 72 , the module 8 constituting the power conversion device 100 , the half-bridge switching element 66 constituting the power conversion device 200 , and the inverters 62 and 63 .

The fin 72 is located in the water path 13 on the projection surface of the half-bridge switching element 66 and the inverters 62 and 63 , and the module 8 is arranged on the projection surface of the fin 72 . The cooling water enters the water channel 13 from the inlet 14 and flows to the outlet 15 through the area where the fins 72 are located. Generally speaking, in an electric vehicle, the power conversion device 200 for driving the electric motors 60 and 61 as the power of the electric vehicle is compared with the power conversion device 100 as a DC/DC converter for charging the lead battery. Therefore, in order to downsize the half-bridge switching element 66 and the inverters 62 and 63 that constitute the power conversion device 200, fins are provided in the water passage 13 on the side where the power conversion device 200 is installed. 72.

According to this embodiment, the module 8 constituting the power conversion device 100 is mounted on one first surface 68 of the flat water channel 13 , and the half-bridge switch constituting the power conversion device 200 is mounted on the other second surface 69 . Since the components 66 and the inverters 62 and 63 can effectively use both surfaces of the water passage 13 as cooling surfaces, the cooler composed of the housing 12 and the water passage 13 can be miniaturized and the cost of the cooler can be reduced. . In addition, it is not necessary to provide the water passage 13 in each of the power conversion device 100 and the power conversion device 200, so that the cost of the water passage 13 can be reduced. In the present embodiment, an example is shown in which the half-bridge switching element 66 and the inverters 62 and 63 constituting the power conversion device 200 are mounted on the second surface 69 . However, even if the input capacitor 64 and the booster are mounted, The reactor 65 and the filter capacitor 67 also have the same effect.

In addition, since the cooling surfaces of the modules 8 constituting the power conversion device 100 and the cooling surfaces of the half-bridge switching elements 66 and the inverters 62 and 63 constituting the power conversion device 200 are arranged in opposite directions, it is possible to have a simple structure. The larger flat surface of the structurally flat water channel 13 is used as a cooling surface, thereby reducing the cost of the cooler composed of the housing 12 and the water channel 13.

In addition, since the inverter 4 and the rectifier circuit 5 of the module 8 constituting the power conversion device 100 are arranged in the same direction as the half-bridge switching elements 66 and the inverters 62 and 63 constituting the power conversion device 200, therefore The long-side direction of the cooling area required for the module 8, the half-bridge switching element 66, and the inverters 62 and 63 can be unified with the long-side direction of the water channel 13, thereby reducing the cooling area of the water channel 13 and reducing the cost of the casing. 12 and water line 13 constitute the cost of the cooler.

In addition, since the cooling water is arranged in the direction of the inverter 4 and the rectifier circuit 5 constituting the module 8 of the power conversion device 100, and the half-bridge switching element 66 and the inverters 62 and 63 constituting the power conversion device 200, Since the inverter 4 and the rectifier circuit 5 of the module 8, the half-bridge switching element 66, and the inverters 62 and 63 flow in a direction perpendicular to the arrangement direction, they are not cooled by the temperature rise caused by the heat generated by each other. The influence of water can suppress the temperature rise of the cooling water, and the module 8 or the half-bridge switching element 66 and the inverters 62 and 63 can be miniaturized. As a result, the cooler composed of the casing 12 and the water passage 13 can be miniaturized, and the cost of the power conversion device 100 and the power conversion device 200 can be reduced.

In addition, since the modules 8 constituting the power conversion device 100 are arranged on the projection surface of the fins 72 , the cooling capacity of the mounting surface is lower than that of the modules 8 constituting the power conversion device 100 on the side where the fins 72 are not provided. It is also increased by the cooling water whose flow rate is increased due to the fins 72 . Thereby, the heat-generating components of the power conversion device 100 represented by the module 8 and located on the projection surface of the fin 72 can also be miniaturized, thereby reducing costs.

In addition, since part of the transformer 2 or the filter reactor 6 constituting the power conversion device 100 is located outside the projection plane of the water channel 13 or the fin 72, the cooling area relative to the height can be larger than that of the transformer 2 or the filter reactor 6. Therefore, The inverter 4 and rectifier circuit 5 of the module 8 with higher efficiency are cooled by the flat water channel 13, or the half-bridge switching element 66 and the inverters 62 and 63 are preferentially arranged in the flat water channel 13. This allows the module 8 or the half-bridge switching element 66 and the inverters 62 and 63 to be miniaturized. Therefore, the cooler composed of the casing 12 and the water passage 13 can be miniaturized, and the cost of the power conversion device 100 and the power conversion device 200 can be reduced.

In this embodiment, the flat water passage 13 is shown as an example in which the water passage for cooling the power conversion device 100 and the water passage for cooling the power conversion device 200 are the same. However, as shown in FIG. 8 , the water passage may be the same. In the water channel 13, the water channel 13 is divided by disposing the partition plate 73 of the housing 12 on a surface parallel to the plane of the water channel 13. The water channel for cooling the module 8 constituting the power converter device 100 is divided into a water channel for cooling the module 8 constituting the power converter device 100. The half-bridge switching element 66 and the water path of the inverters 62 and 63 are separated.

As described above, even in a structure in which an optimal water path can be applied to the module 8, the half-bridge switching element 66, and the inverters 62 and 63, both surfaces of the water path 13 are effectively used as cooling surfaces. The cooler composed of the casing 12 and the water passage 13 can be miniaturized, and the cost of the cooler can be reduced.

In this embodiment, an example is shown in which the projection surfaces of the module 8 constituting the power conversion device 100, the half-bridge switching element 66 constituting the power conversion device 200, and the inverters 62 and 63 overlap. However, it may also be possible. The area where the projection surfaces do not overlap. Since thermal interference between the module 8 and the half-bridge switching element 66 and the inverters 62 and 63 is reduced, temperature rise can be suppressed. In addition, the module 8 or the half-bridge switching element 66 and the inverters 62 and 63 can be miniaturized, and the cooler composed of the casing 12 and the water passage 13 can be miniaturized. Thereby, the cost of the power conversion device 100 and the power conversion device 200 can be reduced.

In this embodiment, an example is shown in which the boost chopper and the inverters 62 and 63 are used as the power conversion device 200. However, the boost chopper may not be used, or it may be one inverter. In addition, the power conversion device 200 may also be a vehicle-mounted charger. In this case, the input of the on-board charger is the AC voltage of the system, and the output is connected to the DC power supply 1, so the power conversion device 200 is configured to connect the output of the on-board charger.

Although various exemplary embodiments and examples are described herein, the various features, manners, and functions described in one or more embodiments are not limited to application to a particular embodiment and may be used individually or in various combinations. applied to the implementation. Therefore, numerous modifications that are not illustrated are conceivable within the technical scope disclosed in this application. For example, this includes a case where at least one component is modified, added, or omitted, and a case where at least one component is extracted and combined with components of other embodiments.

Hereinafter, various aspects of the present disclosure are described together as appendices.

(Note 1)

A power conversion device, characterized in that it includes: a plurality of semiconductor switching elements that convert a DC voltage of a DC power supply into an AC voltage;

an insulating transformer that transmits the AC voltage from the primary side to the secondary side and outputs it; and

a rectifier circuit containing a plurality of rectifier elements for rectifying the output,

The plurality of semiconductor switching elements and the plurality of rectifying elements are composed of modules sealed in the same package.

(Note 2)

The power conversion device according to Appendix 1, wherein the plurality of semiconductor switching elements constitute a full-bridge circuit.

(Note 3)

The power conversion device according to Appendix 1 or Appendix 2, wherein the plurality of rectifying elements are diodes.

(Note 4)

The power conversion device according to any one of appendices 1 to 3, wherein the module includes: a cooling member for cooling the plurality of semiconductor switching elements and the plurality of rectifying elements; and an insulating member for insulating at least one of the plurality of semiconductor switching elements and the plurality of rectifying elements from the cooling member.

(Note 5)

The power conversion device according to any one of Supplementary Notes 1 to Supplementary Notes 4, wherein the module has external terminals connected to the plurality of switching elements, the plurality of rectifying elements and an external circuit,

The external terminals are arranged on at least two sides of the module.

(Note 6)

The power conversion device according to appendix 5, wherein the external terminal is configured to include a primary-side external terminal connecting the plurality of switching elements and the external circuit, and a primary-side external terminal connecting the plurality of rectifying elements and the external circuit. The secondary side external terminals of the external circuit are arranged on both sides of the module with mounting areas of the plurality of switching elements sandwiched between them, and the secondary side external terminals sandwich the plurality of rectifiers. Mounting areas for components are arranged on both sides of the module.

(Note 7)

The power conversion device according to appendix 6, wherein the primary side external terminal and the secondary side external terminal are arranged in a mounting area corresponding to the plurality of switching elements and the mounting area of the plurality of rectifying elements. The regions are arranged in the same direction.

(Note 8)

The power conversion device as described in appendix 6 or 7, characterized in that, among the primary side external terminals, a primary side DC input terminal connected to the DC power supply is arranged on the first side of the module and connected to the The primary side AC output terminal of the insulation transformer is arranged on a surface opposite to the first side surface.

(Note 9)

The power conversion device according to appendix 6 or 7, wherein among the secondary side external terminals, the secondary side AC input terminal connected to the insulation transformer is arranged on the second side of the module, and A secondary-side DC output terminal connected to a load via the rectifier circuit is arranged on a surface opposite to the second side surface.

(Note 10)

The power conversion device according to any one of appendices 6 to 9, wherein one of the primary side external terminals is connected to the primary side AC output terminal of the insulation transformer and the secondary side external terminal. The secondary side AC input terminals connected to the isolation transformer are configured on the same side of the module.

(Note 11)

The power conversion device according to any one of appendices 1 to 10, characterized in that the power conversion device includes the module, the insulation transformer, and a cooler for cooling the rectifier circuit.

(Note 12)

The power conversion device according to appendix 11, characterized in that the power conversion device is configured in combination with a second power conversion device, and the module is mounted on the first surface of the cooler, as a function of the At least one heat-generating component constituting the second power conversion device is mounted on a second surface opposite to the first surface.

(Note 13)

The power conversion device according to Appendix 12, wherein the heat-generating component is a plurality of semiconductor switching elements constituting the second power conversion device.

(Note 14)

The power conversion device according to Appendix 13, wherein the cooling surface of the module faces the cooling surface of the plurality of semiconductor switching elements constituting the second power conversion device via the cooler.

(Note 15)

The power converter device according to appendix 13, wherein the arrangement direction of the mounting regions of the plurality of semiconductor switching elements and the mounting regions of the plurality of rectifier elements constituting the power conversion device is the same as that of the mounting regions constituting the second power converter. The plurality of semiconductor switching elements of the conversion device are arranged in the same direction.

(Note 16)

The power conversion device according to any one of appendices 11 to 15, characterized in that the cooler has a water passage, and the flow direction of the refrigerant flowing in the water passage is perpendicular to the direction constituting the power conversion device. The direction of the arrangement direction of the mounting areas of the plurality of semiconductor switching elements and the mounting areas of the plurality of rectifying elements.

(Note 17)

The power conversion device according to any one of appendices 12 to 15, wherein when viewed from a stacking direction in which the module and the cooler are stacked, at least a part of the module is disposed on the second The areas of the cooling fins in the cooler on the power conversion device side overlap.

(Note 18)

The power conversion device according to any one of Supplementary Notes 11 to 15 and 17, wherein the cooler has a water path, and the insulation transformer is used to filter the output current of the plurality of rectifying elements. When viewed from the stacking direction of stacking the modules and the cooler, at least a part of the filter reactor is located outside a certain area of the water passage.

Label description

1 DC power supply, 2 transformer, 2a primary winding, 2b secondary winding, 3 load, 4 inverter, 4a~4d semiconductor switching elements, 5 rectifier circuit, 5a, 5b diodes, 6 filter reactor, 7 filter capacitor, 8 Module, 9 cooling plate, 10 insulation component, 11 resin, 12 shell, 13 water path, 14 inlet, 15 outlet, 16 base plate, 17 wiring, 18, 53~56 terminals, 19 cooling component, 40a~40d gate pad , 41a~41d source pad, 42a~42d, 43, 44, 45a~45d, 46a~46d, 47a, 47b lead frame, 48a~48d, 49a~49d, 50a~50d, 52a, 52b wire bonding, 51a , 51b anode pad, 60, 61 motor, 62, 63 inverter, 64 input capacitor, 65 boost reactor, 66 switching element, 67 filter capacitor, 68 first surface, 69 second surface, 70 second cooling Components, 71 third surface, 72 fins, 73 partitions, 100, 200, 300 power conversion devices, Vin, Vout DC voltages.

Claims (18)

1. A power conversion apparatus, comprising:

a plurality of semiconductor switching elements that convert a direct-current voltage of a direct-current power supply into an alternating-current voltage;

an insulation transformer which transmits the alternating voltage from a primary side to a secondary side and outputs the alternating voltage; and

a rectifying circuit including a plurality of rectifying elements rectifying the output,

the plurality of semiconductor switching elements and the plurality of rectifying elements are constituted by modules sealed in the same package.

2. The power conversion device of claim 1, wherein,

the plurality of semiconductor switching elements constitutes a full bridge circuit.

3. A power conversion apparatus according to claim 1 or 2, wherein,

the plurality of rectifying elements are diodes.

4. A power conversion apparatus according to claim 1 or 2, wherein,

the module comprises: a cooling member for cooling the plurality of semiconductor switching elements and the plurality of rectifying elements; and an insulating member for insulating at least any one of the plurality of semiconductor switching elements and the plurality of rectifying elements from the cooling member.

5. A power conversion apparatus according to claim 1 or 2, wherein,

the module has external terminals connecting the plurality of switching elements, the plurality of rectifying elements and an external circuit,

the external terminals are disposed on at least two sides of the module.

6. The power conversion device of claim 5, wherein,

the external terminal includes a primary external terminal connecting the plurality of switching elements and the external circuit, and a secondary external terminal connecting the plurality of rectifying elements and the external circuit, the primary external terminal being disposed on both side surfaces of the module with the mounting regions of the plurality of switching elements interposed therebetween, and the secondary external terminal being disposed on both side surfaces of the module with the mounting regions of the plurality of rectifying elements interposed therebetween.

7. The power conversion device of claim 6, wherein,

the primary-side external terminal and the secondary-side external terminal are arranged in the same direction as the arrangement direction of the mounting regions of the plurality of switching elements and the mounting regions of the plurality of rectifying elements.

8. The power conversion device of claim 6, wherein,

Among the primary-side external terminals, a primary-side dc input terminal connected to the dc power supply is disposed on a first side surface of the module, and a primary-side ac output terminal connected to the insulation transformer is disposed on a surface opposite to the first side surface.

9. The power conversion device of claim 6, wherein,

among the secondary-side external terminals, a secondary-side ac input terminal connected to the insulation transformer is disposed on a second side surface of the module, and a secondary-side dc output terminal connected to a load via the rectifier circuit is disposed on a surface opposite to the second side surface.

10. The power conversion device of claim 6, wherein,

a primary-side ac output terminal of the primary-side external terminals connected to the insulation transformer and a secondary-side ac input terminal of the secondary-side external terminals connected to the insulation transformer are arranged on the same side of the module.

11. A power conversion apparatus according to claim 1 or 2, wherein,

the power conversion device includes the module, the insulation transformer, and a cooler for cooling the rectifying circuit.

12. The power conversion device of claim 11, wherein,

the power conversion device is configured in combination with a second power conversion device, the module is mounted on a first surface of the cooler, and at least one or more heat generating components that configure the second power conversion device are mounted on a second surface that is a surface opposite to the first surface.

13. The power conversion device of claim 12, wherein,

the heat generating component is a plurality of semiconductor switching elements constituting the second power conversion device.

14. The power conversion device of claim 13, wherein,

the cooling surface of the module is opposed to the cooling surfaces of the plurality of semiconductor switching elements constituting the second power conversion device via the cooler.

15. The power conversion device of claim 13, wherein,

the mounting regions of the plurality of semiconductor switching elements and the mounting regions of the plurality of rectifying elements constituting the power conversion device are arranged in the same direction as the arrangement direction of the plurality of semiconductor switching elements constituting the second power conversion device.

16. The power conversion device of claim 11, wherein,

The cooler has a water path in which a flow direction of a refrigerant flowing therein is a direction perpendicular to an arrangement direction of mounting regions of a plurality of semiconductor switching elements and mounting regions of a plurality of rectifying elements constituting the power conversion device.

17. The power conversion device of claim 12, wherein,

at least a part of the module overlaps with a region of a cooling fin provided in the cooler on the second power conversion device side, as viewed from a lamination direction in which the module and the cooler are laminated.

18. The power conversion device of claim 11, wherein,

the cooler has a water path, and the insulation transformer or a filter reactor for filtering the output currents of the plurality of rectifying elements is located at least partially outside a certain region of the water path when viewed from a lamination direction in which the module and the cooler are laminated.